A geologist has collected 25 specimens of basaltic rock and and 16 specimens of granite. The geologist instructs a laboratory assistant to randomly select 10 of the specimens for analysis. (a) What is the probability that at least 3 of the selected specimens are granite? (b) What is the expected number of granite specimens in the sample? (c) If this same process is repeated every day, how many days (on average) will it take before getting a sample consisting entirely of granite?